Hearing aids for compensating a wearer's hearing loss are well known. The present invention is particularly related to such kinds of hearing devices. However, the present invention may also be implemented in other types of hearing devices, hearing instruments or hearing aids which comprise a connecting element between two physical parts of the device, e.g. a headset, a headphone, ear protection plugs, etc. In the following the terms “hearing device” or “hearing aid” refer to devices in general which are related to providing an acoustic signal to a user's ear.
Hearing devices, in particular hearing aids, are very dense applications and when integrating wireless applications, it may sometimes be difficult to find sufficient space for required or desired antenna components.
It is widely known that an integration of wireless systems into hearing instruments requires integration of antenna structures as well, if bulky external antenna solutions are to be avoided. The efficiency of the antenna and the wireless system is important, as low battery consumption is commonly a design parameter. Various configurations of hearing aids as examples of hearing devices are known, such as cochlear, in-the-ear (ITE), completely-in-canal (CIC), behind-the-ear (BTE), and receiver-in-the-ear (RITE) (the latter sometimes termed ‘receiver in the canal’).
The efficiency and bandwidth of antennas for electro-magnetic fields depend strongly on the size relative to a wavelength of the signal or field. However, common hearing instruments are typically much smaller than the wavelength in the appropriate frequency bands, which has a disadvantageous effect on the efficiency and bandwidth of the antennas build into the common hearing devices.
Additionally, an antenna comprising multiple electrically conducting elements having multiple purposes, such as being part of the antenna and carrying a signal to for example an output transducer, it is known that adding more electrically conducting elements to the antenna will have a severe impact on the bandwidth of the antenna.